See bug 893662 regarding upstream recommendations for distros. Should we pass --enable-checks by default? Or a default-on USE flag? They're lightweight assertions. https://bugs.freedesktop.org/show_bug.cgi?id=92546 describes them as: """ * "assertions", analogous to Standard C assert() and GLib g_assert(). We recommend to distributions that these should be disabled for production builds, analogous to Standard C -DNDEBUG. If enabled, assertion failures are always fatal. * "checks", analogous to GLib g_return_if_fail() and g_return_val_if_fail(). We recommend that these are enabled for production builds. If enabled, they are fatal by default; they can be made non-fatal by setting the environment variable DBUS_FATAL_WARNINGS to 0, or made fatal by setting it to 1. """ (That source may be a bit dated though.)
